Strength and flexibility of the lower body are important to everyone. Strength and flexibility in the feet, ankles, knees, thighs and hips can reduce the possibility of injury or strain from engaging in various sporting activities. On the other hand, to those who have suffered an injury to the lower extremities, a program of exercise which both strengthens and improves joint mobility can be critical in recovering full use of the extremities and in preventing recurrence of ankle, knee and joint strains and injuries.
Those involved in sporting activities, for example skiing, biking, roller blading, ice skating, etc., have long known of the benefits of warmup and other stretching exercises to reduce the possibility of injury by imparting greater strength and mobility, particularly with respect to the lower extremities of the body.
Tendons, the connective structures of the body, link together the various bones and joints within the body. Muscles provide the motive power for the joints. Muscles can be strengthened by exercise and tendons can be lengthened by repeated stretching. Greater muscular strength allows the body to resist excessive motion between bodily joints. Increased flexibility or tendon length allows a greater range of movement of the joints before damage is sustained by the body.
A full range of motion of the joints of the lower extremities is extremely important to mobility which, in turn, has a major impact on the quality of life. For those who have suffered injuries which interfere with mobility there is a very real need to recover the mobility. Such recovery of mobility can often be achieved through exercise which builds joint strength and flexibility.
One exercise device which is known for exercising the lower extremities consists of a board supported on two rockers. The exercise is performed by standing on the board while grasping a stationary object and rocking back and forth on the board. Thus, the upper portion of the body is held substantially vertical while the lower portion of the body conforms to the inclined surface produced by the board rocking back and forth. The orientation of the body with respect to the direction of rocking may be varied so the joints of the lower extremities receive a full range of motion.
Existing boards with rockers are not specifically designed to increase the range of motion of joints. Particularly, they do not provide a means whereby the maximum extent of the joints may be approached gradually and the joint held in that position of maximum extension for a period of time.
What is needed is an exercise device for extending the range of joint motion.